This invention relates to a vacuum insulating glass (IG) unit with polymer inclusive spacers.
Vacuum IG units are known in the art. For example, see U.S. Pat. Nos. 5,664,395, 5,657,607, and 5,902,652, the disclosures of which are all hereby incorporated herein by reference.
Prior art FIGS. 1-2 illustrate a conventional vacuum IG unit. IG unit 1 includes two spaced apart glass substrates 2 and 3 which enclose an evacuated or low pressure space 6 therebetween. Glass sheets/substrates 2 and 3 are interconnected by peripheral or edge seal of fused solder glass 4 and an array of support pillars or spacers 5.
Pump out tube 8 is hermetically sealed by solder glass 9 to an aperture or hole 10 which passes from an interior surface of glass sheet 2 to the bottom of recess 11 in the exterior face of sheet 2. A vacuum is attached to pump out tube 8 so that the interior cavity between substrates 2 and 3 can be evacuated to create a low pressure area or space 6. After evacuation, tube 8 is melted to seal the vacuum. Recess 11 retains sealed tube 8. Optionally, a chemical getter 12 may be included within recess 13.
U.S. Pat. No. 5,644,395 discloses that spacers 5 are made of solder glass, glass, ceramic, or metal.
Unfortunately, these materials tend to be very hard and rigid, thereby leading to a potential for glass cracks in the substrates proximate the spacers/pillars. The potential for substrate cracking proximate the spacers/pillars may be reduced by tempering the glass substrates, but this is expensive.
It will be apparent to those of skill in the art that there exists a need for a vacuum IG unit, and corresponding method of making the same, where the spacers are made of a flexible material that reduces the potential for glass cracking but which can withstand the atmospheric pressure outside the unit causing compression thereof.
An object of this invention is to provide a vacuum IG unit with polymer inclusive spacers.
Another object of this invention is to provide a vacuum IG unit with flexible spacers, which reduce the likelihood of glass cracking proximate the spacers.
Another object of this invention is to fulfill one or more of the above listed objects and/or needs.
Generally speaking, this invention fulfills one or more of the above listed needs and/or objects by providing thermally insulating panel comprising:
first and second spaced apart glass substrates having a low pressure space therebetween having a pressure less than atmospheric pressure;
a hermetic seal provided between said first and second substrates for sealing off said low pressure space; and
a plurality of polymer inclusive spacers provided between said first and second substrates for spacing the substrates from one another.
In certain embodiments, the spacers are of or comprise a polymer selected from the group consisting essentially of: polyimide, polyamide, polyether-imide, polysiloxane, polyphenylene, polyphenylene oxide, polyaramide, polysulfone, and polycarbonate.
In certain embodiments, do not melt or physically deform to any significant extent upon exposure to temperatures up to 350 degrees C., more preferably up to 290 degrees C.